This section provides background information related to the present disclosure which is not necessarily prior art.
Mechanical transmissions typically include an input shaft fixed to an input gear that is meshingly engaged to an output gear fixed to an output shaft in order to transmit torque between the input and output shafts. The geometry of the gear teeth, tolerances, and/or wear of the gear teeth can result in backlash or play between the input and output gears. Backlash between the input and output gears can result in undesirable noise, vibration, and/or harshness (“NVH”) during load cycling of the transmission or when reversing the rotational direction of the input shaft, as the backlash must be taken up before torque can be transferred between the input and output gears. In vehicles which employ an electric motor for propulsive power or for torque vectoring, the electric motor typically is drivingly coupled to a mechanical transmission to provide torque thereto on an as-needed basis. The electric motor can be operated in an intermittent fashion and can frequently change rotational direction (e.g. based on tractive need and/or whether the vehicle is making a right or left turn), which can result in undesirable NVH due to backlash in the mechanical transmission.